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6100 doesn't see drive on SCA->50pin adapter

Mr. Ksoft

Well-known member
I've been having bits and pieces shipped in this week and I'm testing them on my 6100. Since the hard drive is ridiculously limited, I bought an SCA drive and an adapter since I had read that this works.

Image of drive

Image of adapter (50pin side)

Image of adapter (SCA side)

So I plugged it in, and the system doesn't recognize it at all. It simply does not show up in anything. The drive does spin up properly and I hear it running just as any typical drive should, no weird sounds or anything. I've tried using HD SC Setup, Drive Setup (patched for non-Apple drives and non-patched), and also Lido 7. No errors either, just a blank spot. I have played with the setup a bit-- obviously with my current drive as SCSI ID 0 I set the adapter to ID 1 as a test (nothing), then 2 (nothing), even 3 since the CD drive had to be disconnected (nothing again). I also tried completely removing the main drive, setting the ID on the adapter to 0, and booting from CD or floppy-- also nothing.

Anyone worked with this before? Am I missing something? I can't say for sure if it is the drive (which seems like it should work being an old server drive and apparently was checked by the seller) or the adapter (which is probably cheap junk simply because they are low-volume sellers). I'm leaning toward the adapter just because of likelihood but I could have a dud drive-- but I don't have any other way of testing. If it's the adapter I would love to be pointed towards one that would work better.

Thanks in advance :)

 

markyb86

Well-known member
as far as I know on this, you need to terminate the SCSI chain either with a passive terminator on the external SCSI port, the end of the internal chain, or on the adapter itself TPR needs to be jumpered.

 

Mr. Ksoft

Well-known member
I guess I assumed that leaving the hard drive or CD drive in would terminate it, especially since the CD drive (AppleCD 300 Plus) appears to have a jumper in the "Term Power" spot. However that may mean something totally different as the similarly labelled "TPR" jumper on the adapter doesn't change anything either. So if it's a termination issue, I might need one of those passive terminators. Where would I find one? I was just surfing eBay and see some 68 pin ones, and a few 50-pin active terminators, but none that are 50-pin and let me pass through to a drive. Obviously I don't want to just terminate one of the ends because then I lose the ability to have both CD and a hard drive at the same time. Unless I'm misunderstanding and that's exactly what I have do. I'll admit I'm not completely sure as I don't have much SCSI experience at all.

 

CelGen

Well-known member
Around the timeframe that 16gb drives came to Ultra320 SCSI manufacturers started dropping automatic backwards compatibility for the older and slower SCSI buses.

Your drive is probably fine however if there is no jumpers to force alternate SCSI modes you're out of luck.

OH SNAP UNISERVER! 8U

 
Last edited by a moderator:

uniserver

Well-known member
In the modern hard drive thread, we were only talking about a specific hard drive.

2.5" u320 IBM eServer drives.

I do not vouch for any other SCA hd.

In-fact I have tried other SCA hard disks a Fujitsu one, and another one forget the brand, and neither of those worked for me in vintage mac's

The magic is in the chipset of the drive its self, wether or not they really did follow the proper backwards compatibility.

It just so happens the drives i'm selling for 30 each. they do work outstanding and are fully backwards compatible.

 

Trash80toHP_Mini

NIGHT STALKER
U160 drives are all backward compatible, that was in the spec. Backward compatibility was dropped from the U320 spec, so it's hit or miss.

It's not like a NuBus Architecture Mac can really make use of the speed more modern SCSI drives afford without a SCSI II expansion card, but the additional capacity nice . . .

. . . so long as it comes in chunks larger than 2MB each! ::)

. . . the similarly labelled "TPR" jumper on the adapter doesn't change anything either.
It only makes a difference if you've got a passthru terminator hooked up to the 50 pin side To PoweR. ;)

Piccie

 

Mr. Ksoft

Well-known member
So it seems it's likely this drive just isn't backwards compatible. Okay. I'll get a U160 drive and... figure out something to do with this one. At least it was only 10 bucks. :p

Is this one likely to work? Ultra160, IBM eServer. Isn't 2.5" or U320 like uniserver endorses, but I don't see any of those available at all. But if U160 is backwards compatible still, should work okay.

Also, should I still get a terminator to go with it?

 

Trash80toHP_Mini

NIGHT STALKER
It was actually James1095 who recommended the 2.5" Seagate Savvio drives. I jumped hard on his recommendation, snagging a batch for myself and uni snagged the batch I'd been watching as backup plan if I didn't win the first auction. With much help from the gang, especially our resident SCSI Voodoo Priest, we got them up and running reliably. I was glad to hear that uni got another batch and is still helping other comrades out with this project.

That said, don't give up on your U320 drive quite yet. Get yourself an internal passthru terminator for testing it, you'll need one to properly configure whatever drive you wind up using anyway. I'd also suggest holding out for a 2.5" drive so you'll have elbow room for the terminator and airspace around the drive. uni was successfully using external terminators/terminated external peripherals as a workaround, but I think it's best to do it according to SCSI spec. Put your termination at the end of the internal chain on the boot drive . . .

. . . that was just about the only thing Apple got right about their SCSI implementations in the 68k era. ::)

 

Mr. Ksoft

Well-known member
Alright, I'll start with the terminator and see what happens and if it doesn't work out I'll move on to trying to land one of those drives, but if neither works out that'll have to be it. My budget is going to run out if I make any more mistakes. At least as a backup I could probably set up a file server and store things on there, but it'll be pretty slow.

 

Trash80toHP_Mini

NIGHT STALKER
You won't know that it's a mistake until you've tried it with termination. Controllers for PCI Macs are inexpensive enough when the time comes if it doesn't work out right now.

 

Mr. Ksoft

Well-known member
Well, received the terminator today. Unfortunately, it makes no difference. Also, a few days ago, there was a guy on my local Craigslist selling 4 IBM eServer 3.5" U320 SCA drives for $5, so I picked them up figuring that since they were close to the 2.5" ones that uniserver endorses, they might work. But, they don't seem to either :( I believe I have this setup right. I have the terminator at the end of the chain right before the adapter, TPR jumper on the adapter is set. ID is set to 0 and I'm booting from a CD set to ID 3 (and loading patched Drive Setup off a floppy). Any other jumpers I might be missing? There are a bunch on the eServer drives as well. (image) Any thoughts or should I throw in the towel and give up on these?

 

Macdrone

Well-known member
It was mentioned above the 320 drives are hit or miss.

Has the motherboard been recapped?

Some newer drives allow for no jumper on the main drive as the cable will select.

I would suggest take a day or two away not thinking of it and come back. Sometimes we are too close to the problem.

 

uniserver

Well-known member
Well first you have to setup your partitions right…. and i only endorse things from me.

When people buy from me they get a working, drop in solution. no monkeying around.

also i would set your ID jumper to 2 or 3

you don't need a terminator with the PM 6100, at-least i don't need one.

Not 100% sure about the TPR jumper try it with or with out.

I use mac os 9 to set up the partitions… using standard , 1.9gb partitions 8.1- 8.1 / 3.9gb

 

Mr. Ksoft

Well-known member
It was mentioned above the 320 drives are hit or miss.
I'm aware. I figured at $5 it was worth a try since the 2.5" variant seems to work.

Has the motherboard been recapped?
I'm afraid not, because I suck at precision work and it's expensive to ship out. Not that I have noticed any other problems in the 5 years I have had this machine, so if the caps are on the way out, they are just now starting to go.

Some newer drives allow for no jumper on the main drive as the cable will select.
What do you mean by this? No jumpers = SCSI ID 0 as far as I'm aware. Are you saying that some drives instead will set their own in that configuration? Either way not sure it matters since other IDs don't seem to work either.

Well first you have to setup your partitions right…
Obviously can't do that unless the computer detects the drive and lets me partition it at all.

also i would set your ID jumper to 2 or 3
Tried. Nothing.

you don't need a terminator with the PM 6100, at-least i don't need one.
Well, I've continued to try with and without my passthru terminator... nothing.

Not 100% sure about the TPR jumper try it with or with out.
No difference either way.

Well, unless there is some crazy revelation, I think I give up. I don't even know why I'm messing with it on here anyway, since it's meant for the Quadra 650 I'm putting together. It should come in in the next few days, so I'll start working with that whenever it shows up. Not that I expect to be anything but disappointed on there either, it's likely to be the same old. Maybe I can get my hands on one of your drives, uniserver, in the future-- for now my budget on this project has dried up.

 

uniserver

Well-known member
I set up the drives in my powermac 7500(/w G3 333 CPU card installed), its running mac os9.

partition it… then drag and drop the os of choice to the first partition… Power down, remove the drive, then install the drive in the vintage machine in need of a drive.

Also your results are consistent with mine, during the whole 3.5" SCA HD experimentation phase i was going through this time last year. Now, I did end up getting a 160 SCSI card for that powermac 7500. and that of corse will show me any modern SCA hd.

but that is not really all that useful.

Maybe we should give more credit to james LOL… haha

Does james want more credit is the question :)

 

NJRoadfan

Well-known member
Has the motherboard been recapped?
Do 6100s have problems with caps to begin with? Mine seems fine.

Quite a few people on various forums over the years have had problems with some SCA adapters simply not working, even with Ultra160 drives. The last bit of SCSI voodoo I had to deal with involved a 68-pin drive in a Powermac 8600, I landed up using a "pigtail" 50-pin terminator at the end of the chain to solve the problems I was having. Also, does the SCA adapter do "high byte" termination? Wide SCSI (16bit) devices can have problems on narrow 8-bit buses since the upper 8-bit data lines are left unconnected. The spec is supposed to accommodate this, but some drives are a royal PITA.

http://www.scio.k12.or.us/shs/staffweb/mettsg/comptec/SCSI/Scsi_termination_tutorial.htm#6

6. Connecting WIDE SCA-2 (80 pin) drives to a NARROW bus (50 pin).
A narrow bus by definition is 50 conductors, but may be either Single Ended (SE) Low Voltage Differential (LVD) or differential (HVD). HVD devices cannot be mixed SE or LVD devices on the same bus. A wide drive can only be added to a narrow bus if the bus is Single Ended (SE).

Check for the presence of term power on pin 26 of the bus, provided by the host, any drive or the backplane.

An adapter is required to convert the SCA-2 80-pin interface to the narrow 50-pin bus connector. The upper byte, or ‘high byte’ of the wide connector, must be terminated with +5volts inside the adapter, because a floating (not connected) data line is an undefined signal level and may cause parity errors. The DIFFSENS line, pin 46 on the 80 pin side, should be grounded for SE operation.

Some SCA-2 adapters also provide bus termination; if the drive is not at the end of the bus check that the termination can be disabled on the adapter.

Check for two terminators, one at each physical end of the bus. Many 50 pin drives found on a narrow bus are internally terminated; check jumper settings to enable/disable.

Active terminators are required if Ultra SCSI speeds (20 Mbytes/sec) or higher are being used.

No more than 8 devices are supported in this configuration; see Table 1.

Check maximum bus (cable) length, as described in Table 1.

Check maximum stub length does not exceed 0.1m (4").

Check SCSI IDs. Each device/adapter must have a unique ID, typically set by jumper.

Check for remote start/start delay jumpers and remove if necessary.

Check for ‘Force SE’, ‘Disable Wide’ jumpers and apply as required.

(back)
 

Mr. Ksoft

Well-known member
Ah, no 8-bit operation would make sense. Shame too, cause that drive is actually extremely quiet for a 10K/3.5" drive.

I've been reading up on these eServer drives I picked up, and they're apparently renamed Ultrastar 146Z10 drives. Can't find anywhere that specifically states 8-bit compatibility, but one of the datasheets I read up on mentioned narrow SCSI mode communications, so I think they "should" be compatible. I imagine, though, that whether they will actually work is going to be completely unpredictable. Could be my adapter, could be the system, who knows. One day the weather will be right and they'll just suddenly start working. Such is SCSI Voodoo!

You may be on to something, though, with the high-byte termination. The adapter likely does nothing, but I have a passthrough active terminator. Unfortunately I have no idea if it does high-byte or not (what do you bet it doesn't though?)

 
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